半导体氧化锌的制备及其光催化性能研究

采用溶剂热法制备不同形貌、不同大小的纳米ZnO粉体,以偶氮染料甲基橙(MO,Methyl Orange)作为光催化试验研究的对象,考察不同ZnO粉体、溶液的不同pH值、溶液的初始质量浓度和ZnO粉体投加量等因素对光催化氧化降解甲基橙的影响。研究结果表明:四种ZnO粉体的光催化性能都很强,纳米ZnO粉体适用于染料废水的光催化氧化;四种样品对MO溶液的脱色率的顺序为,锤状(20 nm)>椭球状(20 nm)>锤状(50 nm～100 nm)>棒状(直径10 nm,长径比10～30);溶液在酸性和pH>9的碱性环境中都较容易降解,pH在9左右是ZnO的等电点,对溶液的脱色率最低;试验确定甲基橙的最佳初始质量浓度为15 mg/L,每升甲基橙溶液最佳ZnO粉体的投加量为1 g。

Study on preparation and photocatalysis of semiconductor ZnO

Solvent-heating method was used to prepared ZnO powder with different morphology and size.Effects of different ZnO powder,solution pH,solution initial concentration,and ZnO powder quantum on the decomposing of methyl orange by photocatalysis oxidation were studied where MO was used as experimental object.The results showed that the photocatalysis capabilities of the four kinds ZnO powder were all strong.Nano ZnO powder was suitable to the photocatalysis oxidation of dye waste water.The decoloring rate order of the four samples for MO solution was: hammer-like(20nm)>ellipsoide-like(20nm)>hammer-like(50nm~100nm)>rod-like ZnO(with diameter 10nm,ratio of length to diameter 10~30).The solution was decomposed easily whether in acid or alkaline(pH>9) environment.As pH=9 was the isoelectric point,the decoloring rate was the lowest.It could be concluded that the optimum initial concentration of MO and ZnO powder added were 15mg/L and 1g/L respectively.